DE 44 37 073 A1, which is incorporated herein by reference in its entirety, discloses a gear unit fitting that is of the type described in the Technical Field section above, and is intended for an adjustable vehicle seat. For DE 44 37 073 A1, the preferred number of teeth of the first ring wheel is 31, that of the pinion on the frame side is 30 and on the output side is 28, and that of the second ring wheel is 29. This results in a reduction of 435. For a reduction ratio close to practical requirements, along with a high blocking moment, high sequential reliability and minimum output play, there is still the need for optimization.